Study finds ‘implicit’ bias in forensic testimony
While many believe forensic testimony is an objective tool helping achieve justice for law enforcement and criminal defendants, a new report says it propagates a “presumption of guilt” for people of color in the criminal justice system.
The report’s authors say government forensic experts are susceptible to implicit racial bias, which taints their supposed scientific analysis of bloodstains, fingerprints, hair, footwear, firearms and toolmark and tire impressions.
Comprehending the full impact of racial bias
After the murders of George Floyd and Breonna Taylor, criminal justice reform has focused chiefly on policing. However, the authors say the potential for bias doesn’t solely exist when officers stop, search and arrest a suspect.
The research shows judges, prosecutors and jurors often accept scientific-sounding evidence without a critical eye. Government experts are usually accepted as neutral parties and objective witnesses who report the “facts” and have no stake in a case’s outcome.
However, researchers say these experts are as susceptible to bias as anyone else. Furthermore, experts in criminal cases may not be reporting neutral science, and their testimony and conclusions are often contaminated by racial bias and other prejudices.
Biographical data often taints investigations
To illustrate their point, the authors say analyzing a bullet from a crime scene may seem like a neutral process. However, examiners usually get the lead suspect’s name, race and background. That information could lead to a result-driven opinion that the suspect fired the gun.
Since no objective standards exist for measuring the marks on a bullet and the human eye sees what it wants to see, an examiner’s conclusions may reflect their own bias favoring guilt, rather than an accurate analysis of whether the bullet marks match or are sufficient to determine someone’s guilt.
Exonerations continue to raise questions
Recent exonerations illustrate the connection between wrongful convictions, faulty forensic testimony and racial bias. One example is the case of a Black man, Patrick Pursley, who served 23 years of a life sentence for a crime he did not commit before a court tossed out his conviction in 2019.
Pursley’s guilt was based on a firearm analyst’s opinion that test-fired bullets from a gun attributed to the suspect matched slugs and cartridges found at the scene. That evidence was determined as “inconclusive” at a post-conviction hearing, and Pursley was released and awarded a certificate of innocence by the court.